Model 625 Superconducting Magnet Power Supply

Model 625 Features

  • 60 A/5 V, bipolar, true 4-quadrant output
  • 0.1 mA output setting resolution
  • Linear regulation minimizes noise
  • Ripple = 0.007% of maximum current (into a 1 mΩ load)
  • 1 mA per hour stability
  • Parallel operation to ±120 A

The Model 625 Superconducting Magnet Power Supply is the ideal supply for small to medium sized superconducting magnets used in high sensitivity materials research applications. The Model 625 is a practical alternative to both the larger, one size fits all, superconducting magnet supplies and the endless adaptations of generic power supplies. By limiting output power, Lake Shore was able to concentrate on the performance requirements of the most demanding magnet users. The resulting Model 625 provides high precision, low noise, safety, and convenience.

Precision in magnetic measurements is typically defined as smooth continuous operation with high setting resolution and low drift. Achieving these goals while driving a challenging load, such as a superconducting magnet, requires a unique solution. The Model 625 delivers up to 60 A at a nominal compliance voltage of 5 V, with the supply acting as either a source or a sink in true 4-quadrant operation. Its current source output architecture with analog control enables both smooth operation and low drift. A careful blending of analog and digital circuits provides high setting resolution of 0.1 mA and flexible output programming.

Lake Shore chose linear input and output power stages for the moderate 300 W output of the Model 625. Linear operation eliminates the radiated radio frequency (RF) noise associated with switching power supplies, allowing the Model 625 to reduce the overall noise in its output and the noise radiated into surrounding electronics.

Safety should never be an afterthought when combining stored energy and liquid cryogens in a superconducting magnet system. The Model 625 incorporates a variety of hardware and firmware protection features to ensure the safety of the magnet and supply. Safety should never be an afterthought when combining stored energy and liquid cryogens in a superconducting magnet system.

Instrument users have come to rely on Lake Shore for convenience and ease of use. The Model 625 includes the features necessary to conveniently manage a superconducting magnet, such as a persistent switch heater output, calculated field reading, current ramping, and quench detection. Computer interfaces are also integrated for automation of the magnet system. The Model 625 is truly an excellent one-box solution for controlling a superconducting magnet.